The present invention relates to locking pins and more particularly to locking pins for use with drilled shafts or studs.
Numerous locking pins for use with drilled shafts or studs are well known in the prior art and are commonly found on sailing craft. All of the prior art devices known to the inventor suffer from one or more of the following faults: they can flap about so that they are easily snagged by control lines or ropes or foul nearby moving parts which are in relative motion, they permit wobble of the body being held on the drilled shaft, they are difficult to apply and/or extract, they have raised portions which can injur persons or be snagged by a line and inadvertently extracted from the stud and/or require space below the member that goes through the hole in the shaft.
It is a primary object of the present invention to provide a locking pin that suffers from virtually none of the above defects.
It is an object of the present invention to provide a locking pin for use with drilled shafts or studs which is easily installed and removed but provides a low profile and is not readily snagged by ropes or control lines.
It is another object of the present invention to provide a locking pin for use with a drilled shaft or stud which permits three points of contact between the pin and the adjacent surface of a body to be retained on the stud and which prevents undesired rotation of the locking pin and if desired exert a spring force against the retained body.
The invention provides a locking pin fabricated from a single length of spring steel wire or material with similar characteristics of strength and resiliency. The length of wire commencing at a first end has a first straight section to be seated in the aperture in a stud or drilled shaft. The straight section ends in a 270.degree. loop that terminates in a U-shaped member having two legs and a base. The two legs lie at right angles to the first straight section and astride the stud and generally in contact therewith. The base of the U-shaped member is spaced several diameters of the wire from the stud so that the length of wire from the end of the 270.degree. loop and the base of the "U" is long enough to provide the resiliency necessary, even with stiff wire, to flex the metal and lift the legs of the U-shaped member above the end of the stud and extract the locking pin. The legs of the U-shaped section of the pin have a dihedral angle with the apex over the first straight section of the device whereby the base of the U and a loop formed at the end of the wire remote from the first end approach and may even contact the adjacent surface of the body to be retained.
A locking pin fabricated as above has a height of only two wire diameters and is not readily snagged, particularly since all ends or edges of the wire are adjacent the surface of the body or are protected by other members that are so adjacent.